Opisthorchiidosis-A Review

Abstract

The discovery history of opisthorchiid flukes dates back more than 200 years. The life cycle of these liver flukes includes prosobranch snails as the first and a big variety of freshwater fish as the second intermediate hosts. Opisthorchis felineus, O. viverrini and Clonorchis sinensis are species of major medical importance, while sporadic cases of human infection with other representatives of this family are also documented in the literature. There are estimations that 17 million people are infected and more than 350 million people are at risk, mainly in Asian countries. Although opisthorchiid flukes live in the bile ducts of the liver and in the gall bladder, they can affect surrounding liver tissue and even other organs. They are also known to induce the production of autoantibodies as well as allergic reactions. However, the main medical significance is their role in the formation of malignant tumors. Since the clinical symptoms are not specific, a diagnosis must be confirmed by parasitological examination or the detection of antibodies. Apart from coproscopical methods, there are more recent and highly specific assays available, like the detection of coproantigen or the detection of DNA. Praziquantel is the drug of choice for the treatment of opisthorchiidosis. In order to prevent infection, consumption of raw flesh of freshwater fish must be avoided.

Rapid Detection and Differentiation ofClonorchis sinensisandOpisthorchis viverriniUsing Real-Time PCR and High Resolution Melting Analysis

“…For example, microscopic examination is cumbersome and time consuming, requiring experienced laboratory technicians, and often it is difficult to distinguish eggs from those of closely related heterophyids, which have similar egg morphologies. Eggs can therefore only be characterised as “ Opisthorchis/Clonorchis -like” eggs [10]. Crude or recombinant antigens have been evaluated for immunodiagnosis; however, the specificity and sensitivity of these methods are still in great need of improvement [11, 12].…”

A large outbreak of Opisthorchis felineus in Italy suggests that opisthorchiasis develops as a febrile eosinophilic syndrome with cholestasis rather than a hepatitis-like syndrome

“…In the European Union, sporadic infections have been reported in Greece and in Germany [4,5]. The acute infection is described as an association of fever, cutaneous rash, abdominal pain, diarrhoea, nausea and vomiting, with or without jaundice.…”

Comparative studies on animal models for Opisthorchis viverrini infection: host interaction through susceptibility and pathology

“…Previous studies have shown that the natural definitive hosts of O. viverrini include human, dogs, and cats (Schuster 2010). For animal model, Syrian hamster have been used (Hutradilok et al 1983;Boonjaraspinyo et al 2011), and recently, gerbils have also been recognized (Boonmars et al 2009a, b;Wonkchalee et al 2011).…”